2006. № 22

In this paper, method of design optimization for main design parameters jet aircraft of the vertical take off and landing (VTOL) with control jet nozzles and modeling of motion were performed. Application of uncertain Lagrange multipliers method was given possibility of analytical solution. Analytic form of model movement was analyzed to have influence for design parameters to flying description.

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The topic of article is selection of rational amount of agricultural airplane carrying capacity, based on weather impact analysis on the annual work content.

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The article is devoted to the researches of the effects of the airplane maneuvering qualities on production per hour of the aerial chemical works using software "Trajectory".

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Results of design-theoretical and experimental research of ejector thrust augmenter characteristics brought. Values of ejection coefficient η = 4.64 and propulsion increase of 50% (propulsion augmentation coefficient δ≅1.5) relative length of ejection channel of L = 6.7 and considering area relation at ejector inlet of were α = 0.042 obtained.

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The new fundamental method of solution of hyperbolic system of differential equations, the characteristic form of which can be a more than quartic polynomial with nonzero coefficients is presented. The method is based on the approximation of full derivatives relations of macroscopic variables. The method has been applied to H.Grad equations. The results of data validation are submitted.

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The present article is the continuation of the articles [1-3], in which the problem of constructing the applicable in practice necessary and sufficient conditions of the positivity (or nonnegativity) of a polynomial in several variables with real coefficients in the positive orthant was investigated. In the articles [1,2] the necessary condition and some sufficient conditions were received. In the article [3] the necessary and sufficient condition was received without any restrictions on the polynomial. But the applicable in practice method of verification of fulfilment of this condition was described in [3] for the special class of the polynomials. One of the basic ideas of this method consists in use of the methods of vector optimization. In the present article the same (as in [3]) necessary and sufficient condition is used and the method of verification of fulfilment of this condition also makes use of the methods of vector optimization. But the verification method prescribed in this article does not require any conditions on the investigated polynomial.

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A common opinion that a moment of the Poynting vector is spin is a common delusion due to a serious defect of the general field theory. We present a circularly polarized Laguerre-Gaussian beam without an azimuth phase structure as evidence of this. It is shown that the moment of the Poynting vector in this beam is an orbital angular momentum, not spin. Meanwhile, this beam, as well as a circularly polarized plane wave, clearly carries spin. But the standard electrodynamics does not sight it. Spin tensor of the standard electrodynamics is zero. So, this delusion causes many conflicts, vagueness, and paradoxes concerning electromagnetic angular momentum. The only way to resolve the paradoxes is to use an electrodynamics spin tensor which we introduced into the electrodynamics and demonstrate in this paper.

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Expressions for a polarized light beam must be corrected to correspond to results of papers.

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The subject of this article is to prove the need of application of H.Grad thirteen-momentum system of equations to describe the heat-conducting viscous gas unsteady flow. The numerical results for the crossflow about a circular cylinder obtained from Navier-Stokes and H.Grad equations are compared. The hypothesis that H.Grad equations have no bifurcation of solution is offered.

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In the article the information technologies for resources saving on large enterprise are represented. Information system ISERS is intended for detailed monitoring the consumption of energy resources on large enterprise. In this system the original technologies of data transmission over the networks of power supply 220/380V (PLC technologies) are used. The equipment of system is executed on digital signal processors and the microcomputers.

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In the article considered using an error-correcting coding at suboptimal receive as a whole for raising noise-immunity in digital channels and brought simulation results for channels with independent errors.

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In the article considered using an error-correcting coding at suboptimal receive as a whole for raising noise-immunity in digital channels and brought simulation results for channels with packet errors.

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