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71.
N. N. Makarov 《Russian Aeronautics (Iz VUZ)》2008,51(1):60-66
The problem is formulated and a technique is revealed for synthesizing the optimal strategy of troubleshooting and constructing an operation algorithm for the information-control system of inspection and diagnostics of the aircraft equipment state. 相似文献
72.
V. A. Ovchinnikov 《Russian Aeronautics (Iz VUZ)》2007,50(2):146-149
We analyze the effect of injection both of uniformly distributed over the entire cylinder surface and of the optimal one on the velocity distribution at the outer border of the boundary layer and, as a result, on friction. 相似文献
73.
The results of studying an incompressible gas flow field in a periodic element of the porous structure made up of the same radius spheres are presented; the studies were based on the solution of the Navier-Stokes equations using FLUENT software. The possibilities to accelerate the solution process with the use of parallel calculations are investigated and the calculation results under changes of pressure differential in the periodic element are given. 相似文献
74.
T. Yu. Gainutdinova 《Russian Aeronautics (Iz VUZ)》2007,50(2):215-217
In this paper, a program package for solving problems in the field of thin-walled three-dimensional FV structure design is described. 相似文献
75.
A. I. Belousov S. V. Falaleev A. S. Vinogradov P. V. Bondarchuk 《Russian Aeronautics (Iz VUZ)》2007,50(4):390-394
Problems arising in introduction of gasodynamic seals in aircraft engines are considered. The operation of a face gasodynamic seal as part of a natural gas pump is analyzed and its efficiency in the presence of oil is shown. 相似文献
76.
A system for measuring the altitude-airspeed parameters of rotorcraft and very light flight vehicles
In this paper, a problem on measuring the altitude-airspeed parameters (AAPs) of rotorcraft and very light flight vehicles is considered. Some ways of improving systems used to measure the parameters of FV elements and units have been determined. Also suggested and substantiated are the principles and designs of the basic variants of these measuring systems as well as the algorithms of their operation. 相似文献
77.
F. Capitanio A. Bazzano P. Ubertini G. De Cesare M. Del Santo A. Tarana A. Joinet 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2006,38(12):2816-2819
On March 2003, IBIS, the γ-ray imager on board the INTEGRAL satellite, detected an outburst from a new source, IGR J17464-3213, that turned out to be an HEAO-1 transient, namely H1743-322. The spectral and temporal evolutions of the source were observed by INTEGRAL in different periods. Also RXTE observed the source for the first time on 2003 March 29 during a PCA Galactic bulge scan. The source flux decayed below the RXTE PCA sensitivity limit in November 2003, then in April 2004 it was again detected by INTEGRAL. On July 3, 2004 the source was again detected by RXTE/PCA at a 2–10 keV intensity of 16 mCrab and on July 7, reached 69 mCrab. Recently, a new outburst was observed on August 2005. We briefly summarise here the behaviour of the source observed by INTEGRAL from March 2003 to August 2005. The new outbursts of the source and the analysis of all the data collected (now public) give a global view of the spectral and time behaviour of this X-ray transient. 相似文献
78.
Yakimenko O.A. Kaminer I.I. Lentz W.J. Ghyzel P.A. 《IEEE transactions on aerospace and electronic systems》2002,38(4):1181-1200
This paper addresses the problem of determining the relative position and orientation of an unmanned air vehicle with respect to a ship using three visible points of known separation. The, images of the points are obtained from an onboard infrared camera. The paper develops a numerical solution to this problem. Both simulation and flight test results are presented. 相似文献
79.
C Lindberg G Horneck 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1995,15(3):277-280
The ESA MarsNet mission proposal consists most probably of a trio of Mars landers. These landers each contain a variety of scientific equipment. The network of stations demands for a definition of its planetary protection requirements. With respect to the MarsNet mission only forward contamination problems will be considered. Future involvement of European efforts in planetary exploration including sample returns will also raise the problem of back contamination. A tradeoff study for the overall scientific benefit with respect to the approximative cost is necessary. Planetary protection guide-lines will be proposed by an interdisciplinary and international board of experts working in the fields of both biology and planetary science. These guide-lines will have to be flexible in order to be modified with respect to new research results, e.g. on adaptation of microorganisms to extreme (space) conditions. Experiments on the survival of microorganisms at conditions of simulated Mars surface and subsurface will have to be conducted in order to obtain a baseline data collection as a reference standard for future guide-lines. 相似文献
80.
Hegg J.W. Smith M.P. Yount L. Todd J. 《Aerospace and Electronic Systems Magazine, IEEE》1995,10(7):31-34
This paper discusses the advantages of incorporating active sidesticks into a modern aircraft cockpit. Active sidestick controllers for manual pilot inputs in pitch and roll are examined for commercial transport aircraft. Options and requirements for sidesticks are reviewed. The recommendation of an active sidestick controller is developed providing both cross-cockpit coupling and autopilot backdrive capability. These characteristics provide pilot cues identical to traditional cable-linked column/yoke configurations 相似文献