2007. № 26

Opportunities of using methodology of the factorial analysis for modeling daily activity of higher school are considered. The author shows that the factorial approach allows to reveal implicit links between investigated parameters, to generalize and simplify model structure, to raise the quality of taken managerial decisions.

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In clause results of an experimental research of issue characteristics NOx of the complex modelling front device in which it was possible to divide process of burning on diffusioneous and homogeneous are presented.

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The computational method of vibration-dynamic condition of aeronautical engineering objects in extraordinary situations is considered. The regression model built based on integration of data obtained from an experiment with similar samples is cited.

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The main outcomes of the spacecraft perturbed motion researches are presented. The author touches upon the effect of the perturbing aerodynamic forces from the atmosphere reactance on the spacecraft orbit evolution. The calculations of the circular orbits of the spacecrafts of different characteristic surfaces and weights are developed. The influence of the Sun activity level on the spacecraft orbit evolution; and the dependence of the perturbing aerodynamic acceleration value on the orbit height.

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Spacecraft perturbed motion is investigated in the paper. The influence of perturbing forces related to the shape irregularity of the Earth on the satellite orbit evolution. The paper contains the results of the spacecraft orbit evolution calculations.

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The article describes the usage of satellites for producing semi-conductors with the molecular beam epitaxy method. The task of finding dependences between the gross weight of the fuel used for interorbital transfer and the molecular screen weight on the operational orbit height is set.

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Wide spreading of holding type enterprises results in necessity of working out improved management instruments for definite sectors of economy and kinds of activity. The article describes development and application experience holding distribution monitoring system based on Balanced Scorecard methodology. The system intends for Russian holding enterprises with high work share in cost price (high technology productions, medical industry, commerce, service). Use of described system has motivated associated companies to target achievement, has put in order intracorporate relations and payment discipline, has helped to achieve considerable improvement of main productivity indexes.

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The solving of mixed boundary value problem for parabolic differential-difference equation by the evident scheme of finite difference method is considered in this article. These problems are interesting because the behavior of their solution in some subregion may depend from its behavior in another subregion. The fact that stability and convergence of the evident scheme for considering problems is arrived if Lax type condition is realized is shown in this article. The factor-method theory is used for convergence proof. These theoretical researches are illustrated by solution graphs that show the specific features of considering problems.

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Improper integrals by Hadamard that are found in mathematical models of aerodynamics and other problems of mathematical physics are studied. The case of a strong singularity at the end of a segment of integration is considered. The fractional degrees of a singularity are researched. The existence theorem of an improper integral by Hadamard in the considered case is proved. Strict definition of an integral in terms of final value by Hadamard for the fractional degrees of a singularity is given. Explicit expression for an integral by Hadamard that doesn't contain improper integrals convenient for application in mathematical models is obtained.

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Improper integrals by Hadamard that are found in mathematical models of aerodynamics and other problems of mathematical physics are studied. The case of a strong singularity inside of a segment of integration is considered. The whole degrees of a singularity are researched. The existence theorem of an improper integral by Hadamard in the considered case is proved. Strict definition of an integral in terms of final value by Hadamard for the whole degrees of a singularity is given. Explicit expression for an integral by Hadamard is obtained. The expression for an integral by Hadamard that doesn't contain improper integrals convenient for application in mathematical models is obtained also.

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Improper integrals by Hadamard that are found in mathematical models of aerodynamics and other problems of mathematical physics are studied. The integral arising at an evaluation of a velocity from a discrete rotational segment in a control point, arranged inside of a rotational stream is considered. Other integrals that are found in problems of numerical modeling of an aerodynamic interference are considered also. Expressions for integrals by Hadamard that doesn't contain derivatives under an integral convenient for a numerical integration are obtained. Procedure of a numerical integration of improper integrals is obtained also and recommendations on its application in mathematical models are given.

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The interpolation of pole's oscillation on an eight-year time interval and the two-year prediction are constructed by means of the basic mathematical model containing Chandler wobble, annual wobble and irregular slow drift (trend) of an average pole of the Earth on the basis of the measurements data of parameters of Earth's rotation by the least squares method . A Comparison of the theoretical curves (prediction) and the realized pole's movement was made on the basis of the data of the International Earth-Rotation Service (IERS). An extended model taking into account lunar perturbations is considered. On the period of beats is shown manifestations of high-frequency lunar wobbles with monthly and fortnight periods and possibility to interpolate these wobbles for a short time interval.

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A realization of the discrete-element method for numerical modeling of two-phase flow of gas- particle mixture is developed. One modeling particle corresponds to one real particle. Particle reflection from body surface, particle rotation and inter-particle collisions are taken into consideration. Numerical simulation of the supersonic two-phase flow over a circular cylinder is carried out. The results are presented to illustrate the influence of inter-particle collisions and particle rotation on parameters of body-flow interaction.

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The procedure and results of a numerical analysis of an aircraft's dynamic state at abnormal falling at a takeoff stage are submitted. The problem about impact of an aircraft's bearing structure by an obstruction reproducing properties of a ground under the given impact's conditions is considered. The problem about non-stationary interaction is solved with use of a of finite element method (FEM) on the basis of which models of a load-bearing structure and an obstruction are designed. Operation is carried out at a support of the Russian Fundamental Researches Fund (the design N 06-08-01005).

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