2001. № 4

Aviation technics and technology

Bratoukhina A. I.

The analysis of pressure in blades of the carrying screw of the helicopter is carried out at their various fastening to the cartridge. The accounts are executed at change of a mode of flight and influence atmospheric turbulence. Accounts with change hard and mass characteristics of the blade also were carried out, by the joint decision of the equations of fluctuations of the blade and equations of balancing of the helicopter. On the basis of the carried out accounts the parameters are established, which influence is most essential, that has allowed to formulate the recommendations for reduction of a level of variable pressure in blades of the carrying screw.

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Bratoukhina A. I.

Clause is devoted to consideration of a question about pressure in the unrotative blade and cartridge of the carrying screw of the helicopter under action of wind loadings. The assumption is made, that the helicopter is on parking and his(its) screw does not rotate. The account was carried out for the carrying screw with out gimbal by fastening of blades. The task about the own and compelled fluctuations of the blade of the helicopter is solved. The deformations and internal efforts (bending moments and pressure in longeron of the blade) are determined. The analysis of results is carried out and the influence fix of the blade in ground conditions of operation is appreciated.

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Space technics and technology

Gouschine V. N.

The problem of unification in tasks of designing unification of vehicle is considered, the mathematical formulation of statements of various variants of a task of unification is given, the technique of a choice of optimum design parameters with the help of uncertain multipliers Lagrang is discussed.

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Gouschine V. N.

The information -computer technology (IC-technology) of development of samples of new engineering as a new direction of wide introduction of computer facilities in scientific researches and construction work is considered. The contents of technological lines and structure of subsystems of industrial complex System of automation of development is submitted.

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Gouschine V. N.

The efficiency of application solid rocket unit of blocks for increase of carrying capacity of existing liquid rockets - carriers is considered. The results are submitted for a rocket - carrier of "Zenith". Is shown, that the increase of weight of useful loading on 45% is possible. The accounts have shown, that the following circuit of work of steps is expedient: the engines of accelerators are included simultaneously with engines of the second step.

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Mathematics. Physics. Mechanics

Leshchinsky K. N.

In the article the numerical scheme of calculation of heat exchange of a dispersiblis material is offered on the basis of solution of a non-stationary problem of heat exchange within the framework of an elementary cell. The given approach allows to determine time of an establishment of homogeneous state of a sample, its effective heat conductivity, and also eliminates the certain reserve connected to a choice of isothermal surfaces in a traditional method. Features of the numerical decision of the given problem are considered: construction of the scheme of finite difference approximation, the amendments permitting to save conservatism of the scheme.

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Khrapko R. I.

Faraday's lines of force are not enough to an adequate graphical representation of electromagnetic fields. It is necessary to use surfaces. The surfaces permit to represent evidently, for example, a generation of a magnetic field by an electric current, or to represent a generation of scalar potential by an electric field. However, strictly speaking, it is necessary to use tubes instead of lines, and bisurfaces instead of surfaces. A conception of differential (exterior) forms and pseudo forms is used for an explanation. We speak that an external differentiation of a form results in its boundary and the integration of a form by the Biot-Savarat formula results in a new form named as termination. The termination of a termination is zero, the same as the boundary of a boundary. A boundary is closed. A termination is sterile. A conjunction is considered. The conjunction converts forms to pseudo forms and back, converts closed forms to sterile forms and back. The conjunction permits to construct chains of the forms.The conjunction differs from the Hodge star operation by an absence of the dualization.

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Control systems

Bolshov O. A., Kuprijanov A. I.

The article contains the problem of estimation of conversational protection transmitted with wide-range modem fr om non-sanctioned reception and determined minimum capacity ( momentum ) signals at the entrance of the interception receiver wh ere no speech intelligibility is provided.

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Surkov V. V.

The analytical way of synthesis of high-speed governors on the basis of use aggregated variable, satisfying to the considered conditions of high-speed governors is offered. The example, illustrating application of an offered way of synthesis is considered.

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Surkov V. V., Suhinin B. V., Lovchakov V. I., Feofilov E. I.

The scientific bases of the theory of designing optimum on accuracy high-speed multidimensional automatic systems are considered. The rather simple engineering way of continuation of the decision of a task of analytical designing of relay governors by methods of dynamic programming of R Bellman or principle of maximum of L.S. Pontrjagin is offered. The example, illustrating application of the offered theory is resulted.

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