Vol 21, No 10 (2015)

Статьи

U -projection for the adjoint representation of the groupGL( n, K)

Vyatkina K.

Abstract

In the paper we study rings and fields of invariants for the adjoint represen- tation of the group GL(n, K) over the field of zero characteristic. The aim of this paper is to construct the special linear operator, we call it U -projector, that maps any polynomial on the matrix algebra to an U -invariant rational function. In this paper we present two different constructions of U -projector. Using the U -projector we obtain the system of generators of the field of U -invariants of the adjoint representation of the group GL(n, K). We obtain the system of genera- tors of the field of U -invariants for the restriction of the adjoint representation to the subgroup of block-diagonal matrices.
Vestnik of Samara University. Natural Science Series. 2015;21(10):9-23
pages 9-23 views

NUMERICAL INVESTIGATION OF THE SHOWALTER - SIDOROV PROBLEM FOR NONLINEAR DIFFUSION EQUATION

Manakova N., Selivanova A.

Abstract

The article concerns a numerical investigation of nonlinear diffusion mod- el in the circle. Nonlinear diffusion equation simulates the change of potential concentration of viscoelastic fluid, which is filtered in a porous media. This equa- tion is a semilinear Sobolev type equation. Sobolev type equations constitute a vast area of non-classical equations of mathematical physics. Theorem of exis- tence and uniqueness of a weak generalized solution to the Showalter - Sidorov problem for nonlinear diffusion equation is stated. The algorithm of numerical solution to the problem in a circle was developed using the modified Galerkin method. There is a result of computational experiment in this article.
Vestnik of Samara University. Natural Science Series. 2015;21(10):24-28
pages 24-28 views

LINEARIZATION OF PFAFF DIFFERENTIAL EQUATIONS FOR THE CONDITIONAL QUANTILE OF MULTIVARIATE PROBABILITY DISTRIBUTIONS

Orlova I.

Abstract

The article is devoted to the task of bringing the point transformations of nonlinear partial differential equations of Pfaff for conditional quantile multi- variate probability distributions to the Pfaff differential equations with constant coefficients. Solutions of the equations of Pfaff with constant coefficients are linear functions representing the conditional quantile of multivariate Gaussian distributions.
Vestnik of Samara University. Natural Science Series. 2015;21(10):29-39
pages 29-39 views

On conditions of solvability of three-dimensional integralsystem in quadratures

Sozontova E.

Abstract

In this paper we consider the system of equations with partial integrals in three-dimensional space. The purpose is to find sufficient conditions of solvability of this system in quadratures. The proposed method is based on the reduction of the original system, first, to the Goursat problem for a system of differential equations of the first order, and after that to the three Goursat problems for differential equations of the third order. As a result, the sufficient conditions of solvability of the considering system in explicit form were obtained. The total number of cases discussing solvability is 16.
Vestnik of Samara University. Natural Science Series. 2015;21(10):40-46
pages 40-46 views

The limits of maximal means and no autonomous differentialinclusions

Filatov O.

Abstract

The existence theorem of the limit of the maximum average for almost periodic functions on a stand-alone solutions of no autonomous differential inclusion, the right part of which depends on the time periodically is proved. The main condition is a condition of multiple attainability for a differential inclusion. This condition is satisfied, for example, for a constant right-hand side, which does not belong to the eigenspace of speeds. The result is related to the theory of averaging of differential inclusions with slow and fast variables.
Vestnik of Samara University. Natural Science Series. 2015;21(10):47-51
pages 47-51 views

MULTIPARAMETRIC ANALYSIS OF THE STRESS FIELD NEAR THE CRACK TIP

Stepanova L., Roslyakov P.

Abstract

The paper is devoted to analytical determination of coefficients of the Williams asymptotic expansion of the stress field in the neighborhood of two collinear crack tips in an infinite plate under mixed mode loading. On the basis of the Kolosof-Muskhelishvili approach the complete asymptotic expansion of the stress field in the vicinity of the crack tips of two collinear cracks of equal lengths under mixed mode loading is derived. The analysis of the higher order terms in the asymptotic expansion series is performed. It is clear that it is necessary to take into account the higher order terms.
Vestnik of Samara University. Natural Science Series. 2015;21(10):52-76
pages 52-76 views

Asymptotics of the stress field near acrack tip under mixed - mode loading: small parameter method

Stepanova L., Yakovleva E.

Abstract

In the present paper approximate analytical and numeric solutions to nonlinear eigenvalue problems arising in nonlinear fracture mechanics in analysis of stress — strain fields near a crack tip under mixed mode loading are presented. Asymptotic solutions are obtained via perturbation method technique (small parameter method). The artificial small parameter is the difference between the eigenvalue corresponding to the nonlinear eigenvalue problem and the eigenvalue related to the linear ”undisturbed” problem. It is shown that the perturbation technique gives an effective method of solving nonlinear eigenvalue problems in nonlinear fracture mechanics. Comparison results of numeric and asymptotic results for different value of the mixity parameter and hardening exponent shows good agreement. Thus the perturbation theory technique for study of nonlinear eigenvalue problems is offered and applied for eigenvalue problems arising from fracture mechanics analysis in the case of mixed mode loading.
Vestnik of Samara University. Natural Science Series. 2015;21(10):77-90
pages 77-90 views

Cases of integrability corresponding to the pendulummotion on the plane

Shamolin M.

Abstract

In this article, we systemize the results on the study of plane-parallel motion equations of fixed rigid body-pendulum which is placed in certain nonconserva- tive force field. In parallel, we consider the problem of a plane-parallel motion of a free rigid body which is also placed in a similar force field. Thus, the non-conservative tracking force operates onto this body. That force forces the value of certain point of a body to be constant for all the time of a motion, which means the existence of nonintegrable servoconstraint in the system. The obtained results are systematized and served in the invariant form. We also show the nontrivial topological and mechanical analogies.
Vestnik of Samara University. Natural Science Series. 2015;21(10):91-113
pages 91-113 views

On the optimal control of the n-fold integrator

Gorelov Y.

Abstract

 The optimal control problem n-fold integrator with arbitrary boundary conditions and functionals of type norms in spaces of Lq[t0; tf ], q = 1; 2;1 is considered. First, it is the problem of minimizing the total controling impulse, which boils down to L1- problem of moments; secondly, the problem of minimizing the maximum values of the control parameter (represented as L1-problem of moments), and, finally, it is the problem of minimizing ”generalized work control” (as L2-problem of moments). Solving problems is obtained by using the method of moments in the form of the maximum principle by N.N. Krasovsky. It is shown that optimal control in the first problem is approximated by a -impulsive control. Conditions for the existence of regular and singular solutions to this problem depending on the boundary conditions are also specified. The general solution of the second problem, which is the conditions for existence of regular and singular solutions and not equivalence with the mutual problem of time-optimal control is obtained. Examples of solution for the considered control tasks are given. In case of a quadratic functional general relations required for constructing a program optimal control were obtained.
Vestnik of Samara University. Natural Science Series. 2015;21(10):114-133
pages 114-133 views

Subharmonic synchronization ofself-oscillations in discrete time

Zaitsev V., Stulov I., Shilin A.

Abstract

Self-oscillations in the system oscillating in discrete time and being under the influence of an external harmonious signal are investigated. As an object of researches the option of discrete map of the oscillator of Van der Pol offered earlier by authors is brought to attention. The modes of synchronous self-oscillations are analysed by means of methods of numerical experiment and harmonic balance. It is established that the effect of subharmonic synchronization in discrete time can be realized at any relation of frequencies of synchronized self-oscillations and the synchronizing signal.
Vestnik of Samara University. Natural Science Series. 2015;21(10):134-142
pages 134-142 views

Study of the derivatives of 1-adamantane carboxylic acid to induced plateletaggregation human in vitro

Gil’mutdinova A., Ermokhin V., Klenova N., Purygin P.

Abstract

The study of condition of the system of hemoglobin, release of peptide com- pounds, and proteolytic activity of human erythrocytes under conditions of hy- perglycemia of varying degrees is carried out. The increase in the level of hy- perglycemia is accompanied by a decrease of affinity of hemoglobin to oxygen and the growth of level of metgemoglobin, the glycosylated hemoglobin level is increased in conditions of severe hyperglycemia. The level of formation of pep- tides in erythrocytes and the level of output of their cells is determined by the increase in trypsin-like activity in cytosol and increased membrane permeability of red blood cells.
Vestnik of Samara University. Natural Science Series. 2015;21(10):143-150
pages 143-150 views

The study of catalytic activity ofcopper nanoparticles in the reaction of hydrogenation of hexyne-1

Mitina E., Filimonov N., Shafigulin R., Bulanova A., Shishkovsky I., Morozov Y.

Abstract

The process of hydrogenation of unsaturated hydrocarbons is one of the main processes of the petrochemical industry. Unsaturated hydrocarbons are practi- cally inseparable from alkanes, which have the same mass, and to obtain high--quality gasoline unsaturated hydrocarbons are to be eliminated. Furthermore, acetylenic hydrocarbons must be removed from an olefinic feedstock, which is intended for the production of polymers. These problems can be solved by using catalysts with different selectivities. The article studied the copper nanoparti- cles in the hydrogenation reaction hexyne-1. The nanoparticles were obtained by means of levitation blasting and mixed with inerton. Analysis of the reaction mixture was performed by means of gas chromatography. We calculated the rate constants at different temperatures and measured the activation energy of the reaction. It is shown that the first hexyne-1 is converted to hexene-1, followed by hexane. Thus, the catalyst shows the analyzed selective properties, which enables selection of the conditions for obtaining the priority of a particular product.
Vestnik of Samara University. Natural Science Series. 2015;21(10):151-159
pages 151-159 views

CREATION OF A TREE OF PHASES OF THE FOURFOLD MUTUAL SYSTEMS Na,Ba∥F,Cl,WO4

Morgunova O., Loseva M., Trunin A., Katasonova E.

Abstract

Multicomponent system is the basis for the development of compositions with
desired properties. Previously, the study of topology of multicomponent systems
was carried out using graph theory (method of indices of vertices). Due to the
complex topological structure of component relationships, the study of such systems
is currently underway with the use of innovative methods: computer simulation
and experimental study using the capabilities of modern hardware and
software of the experiment. In the framework of the innovative methodology of
the study the reciprocal Quaternary system Na,Ba||F,Cl,WO4, at the level splitting
in stable Association phases. The tree phases was confirmed experimentally
by means of DTA and XRD.

Vestnik of Samara University. Natural Science Series. 2015;21(10):160-165
pages 160-165 views

INFLUENCE OF PRESEEDING PROCESSING OF SEEDS OF FLAX ON GROWTH AND BIOCHEMICAL INDICATORS OF SPROUTS

Purygin P., Vasilyeva T., Purygin V., Sovetkin D., Tsaplev D.

Abstract

Due to the continuous reduction of the areas for crops and increase of urban
population, the increase in productivity of crops is especially important
aspect in production of food today. One of problems of agriculture is creation
of conditions for receiving a crop. Quality of a crop of various crops depends on
efficiency of preseeding processing of seeds. This research investigated a method
of impact of preseeding processing of seeds of flax by a complex of physical
factors: ultra-violet radiation, ozone and the magnetic field (MF) with induktion
of 100, 200, 250 and 300 Gs on growth and activity of a catalase and
peroxidase of a plant, and also the maintenance of photosynthetic pigments in
flax sprouts.

Vestnik of Samara University. Natural Science Series. 2015;21(10):166-173
pages 166-173 views

STATE SYSTEM OF HEMOGLOBIN AND THE ACTIVITY OF ENZYMES OF HUMAN ERYTHROCYTES UNDER CONDITIONS OF HYPERGLYCEMIA IN VITRO

Panarina A., Pestryakova A., Sadychova A., Klenova N., Lebedeva E.

Abstract

The study of condition of the system of hemoglobin, release of peptide com- pounds, and proteolytic activity of human erythrocytes under conditions of hy- perglycemia of varying degrees is carried out. The increase in the level of hy- perglycemia is accompanied by a decrease of affinity of hemoglobin to oxygen and the growth of level of metgemoglobin, the glycosylated hemoglobin level is increased in conditions of severe hyperglycemia. The level of formation of pep- tides in erythrocytes and the level of output of their cells is determined by the increase in trypsin-like activity in cytosol and increased membrane permeability of red blood cells.
Vestnik of Samara University. Natural Science Series. 2015;21(10):174-180
pages 174-180 views

GRAPH MODEL OF INTERACTION OF ANTHROPOGENIC AND BIOTIC FACTORS FOR THE PRODUCTIVITY OF THE CASPIAN SEA

Perevaryukha A.

Abstract

In this paper the construction of the graph model, structuring multivariate analytical reports on the interaction of natural and anthropogenic factors in the ecosystem, which were presented in the form of a set of related concepts is presented. In the signed directed graph in the computing environment a propa- gation of pulses from the vertices within the context the study the situation of degradation of sturgeon stocks of the Caspian Sea was analyzed. These species are included in the Red Book since 2010 despite efforts in organizing an ar- tificial breeding of fish. Method of cognitive structurization allowed to reveal hidden feedback loop on the basis of the graph, weakens the reproduction of fish populations and become the cause of overestimation acceptable exploitation of bioresources. An approach of functional iteration for describing the dynamics of population processes with nonlinear function of the efficiency of reproduc- tion was discussed. It is shown that the discrete iteration have contradictory qualitative behavior of the trajectory in terms of biological interpretation of bi- furcations. It is proposed to use the predicative redefined computing structure based on the chart of behaviors for the description chain of regime changes of the simulated process. For this type of structural changes is promising to allocate substantial fluctuations of growth rate in the early ontogenesis of fish.
Vestnik of Samara University. Natural Science Series. 2015;21(10):181-198
pages 181-198 views

EFFECT OF AMBIENT TEMPERATURE ON THE HUMIFICATION OF PLANT LITTER

Simonov Y.

Abstract

Techniques of laboratory microecosystems, small groups of arthropods and physical and chemical studies are shown. On the basis of instrumental studies the effect of temperature on the ratio of the processes of mineralization and humification of plant residues with the participation of small arthropods is computed. Analysis of the results of measurements of indicators of the process of
humification clearly reveals that the temperature of the plant material affects the intensity of humus accumulation and on indicators of the degree of maturity of humus acids. Activity of microarthropods reduces the dependence of accumulation of humus substances on the temperature.

Vestnik of Samara University. Natural Science Series. 2015;21(10):199-205
pages 199-205 views

This website uses cookies

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

About Cookies