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221.
An exact solution of the Navier - Stokes equations is given that describes the vorticity of a viscous incompressible liquid or gas, dissipative mediums, stationary shear counter-current of continuous vortical medium in the absence of the Coriolis field. 相似文献
222.
Based on an integrated approach, we solve the optimization problem for energy content and weight-dimensional characteristics of the electric servo drive by synthesis of structure and analysis of characteristics for different power supplies. The generalized power supply model, developed for different power supply of drive control systems, is given. 相似文献
223.
S.?N.?Grigor’ev V.?A.?DolgovEmail author A.?V.?Krasnov A.?A.?Kabanov N.?S.?Andreev 《Russian Aeronautics (Iz VUZ)》2015,58(2):244-250
A method of technologic audit for technical re-equipment of enterprises is considered. The method developed is intended to verify technological solutions of projects of technical re-equipment of enterprises according to indicators of productivity. 相似文献
224.
A fading memory filter is a least squares estimator (LSE) thatapplies an exponentially decaying weight to past measurements.When compared with a standard Kalman filter, its key advantagesare asymptotic stability and reduced sensitivity to modeling errors.This paper derives a simple solution for a class of fading memoryfilters, resulting in a reduction in computational complexity. Steadystate filter solutions are obtained for second-and third-order filtersused in a global positioning system (GPS) receiver for high dynamicvehicles. 相似文献
225.
Direct Evaluation of Radar Detection Probabilities 总被引:3,自引:0,他引:3
Xiu-Ying Hou Morinaga N. Namekawa T. 《IEEE transactions on aerospace and electronic systems》1987,(4):418-424
A simple and effective procedure for evaluating detectionperformances in radar and sonar detection problems is derived forboth fixed-threshold and adaptive-threshold detection. Using theprocedure, the cumulative probabilities of the test statistic can bedirectly evaluated from the moment generating functions bycalculating residues. The exact formulae for computing the detectionperformances for the chi-square family of fluctuating targets withan integer fluctuation parameter are given in a finite sum formwithout any special functions for both fixed threshold and cellaverageconstant false-alarm rate detection by using the methoddeveloped here. 相似文献
226.
Transient performance of a single-axis rate gyroscope mounted in a spacecraft which is spinning about the spin axis of the gyro is presented. Analytical expressions for various time-domain and frequency-domain specifications as functions of the spin rate of the vehicle are obtained. Numerical results are presented which are useful in selecting the gyro parameters if it is to be used for the measurements of the angular velocity in spinning space vehicles. 相似文献
227.
An alternative expression for the false alarm probability ofclutter map constant false alarm rate (CFAR), as derived by Nitzberg, is suggested. The new expression converges more rapidly. 相似文献
228.
Powered by free-piston Stirling engines, linear alternators are proposed for space power stations as well as for isolated domestic applications, automotive, and on-Earth solar power plants. As the literature on the subject is sparse and base-design oriented, we present the general equations for both three-phase and single-phase winding configurations having permanent-magnet field excitations. 相似文献
229.
Basic design guidelines are presented for a three-phase tubular linear alternator (LA). A numerical example for the design of a 25 kVA, 14.4 mls, 120/220 V, 60 Hz alternator is used to illustrate the procedure. 相似文献
230.
Richard I. Klein Maxwell T. Sandford II Rodney W. Whitaker 《Space Science Reviews》1980,27(3-4):275-282
Two-dimensional calculations of ionization-shockwave propagation into a curved molecular cloud are presented. Density enhancement occurs due to the combined effects of cloud curvature and radiation flow. The star formation process is expected to be enhanced near the edges of irregularly shaped molecular clouds.Authors listed alphabetically 相似文献